In-Place Cloud Instance Restore

ABSTRACT

The disclosed technology teaches recovering a first virtual machine or an instance with an Internet Protocol address, a first root volume and one or more data volumes that are corrupted. The first virtual machine is hosted by a first cloud server that hosts plurality of virtual machines. The disclosed technology includes instructing the first cloud server to launch a recovery virtual machine. The recovery virtual machine launches one or more new data volumes based upon captured file system images in one or more snapshots taken of corrupted data volumes of the first virtual machine prior to becoming corrupted. The recovery virtual machine detaches the corrupted data volumes and attaches the new data volumes launched to the first virtual machine. The Internet Protocol address of the first virtual machine remains unchanged.

RELATED APPLICATIONS

This application is related to U.S. Nonprovisional patent applicationSer. No. 14/628,022 entitled “Deduplication of Virtual Machine Content,”by Arvind Jain et al., filed Feb. 20, 2015, which is incorporated byreference herein.

This application is related to U.S. Nonprovisional patent applicationSer. No. 14/628,001 entitled “Data management system,” by Arvind Jain etal., filed Feb. 20, 2015, which is incorporated by reference herein.

This application is also related to U.S. Provisional Patent ApplicationNo. 62/570,436 entitled “Incremental File System Backup Using aPseudo-Data volume,” by Soham Mazumdar, filed Oct. 10, 2017, which isincorporated by reference herein.

This application is related to U.S. Nonprovisional patent applicationSer. No. 14/628,019 entitled “Converged Search and Archival System,” byArvind Jain et al., filed Feb. 20, 2015, which is incorporated byreference herein.

FIELD OF THE TECHNOLOGY DISCLOSED

The technology disclosed generally relates to computer or digital dataprocessing systems that include processes or apparatus for establishingoriginal operating parameters or data for a computer or digital dataprocessing system, such as, allocating extended or expanded memory,specifying device drivers, paths, files, buffers, disk management,instances of virtual machines; changing system settings or operationalmodes in a computer or digital data processing system after they havebeen set; increasing a system's extension of protection of systemhardware, software, or data from maliciously caused destruction,unauthorized modification, or unauthorized disclosure; modifying orresponding to the available power to a computer or digital dataprocessing system or programmable calculator; synchronization of two ormore processors; wherein there is a significant temporal, incremental orsequencing control provided to one or more computers, digital dataprocessing systems, processors, memory, or peripherals, or to datatransmission between these systems or components; and more particularlyrelates restoring corrupted virtual machines running on cloud servers.

BACKGROUND

A virtual machine is an emulation of a computer system that, like aphysical computer, runs an operating system and applications. A virtualmachine has virtual devices that provide the same functionality asphysical hardware of a physical computer, and have additional benefitsin terms of portability, manageability, and security. A computingservice provider hosts one or more virtual machines. Virtual machinesare usually backed up by the physical resources of their hostingcomputing service provider.

The computing service provider may be a local data center. A local datacenter is a facility consisting of networked computers and storages thatorganizations or other entities own and use to organize, process andstore large amounts of data. The local data center is physicallyassessable to its owner.

The computing service provider may also be a cloud server. Some cloudservers may be owned and operated by third party providers and leased tothe end user. Organizations and other entities can sign up as clients onone or more cloud servers. A cloud server enables ubiquitous,convenient, on-demand network access to a shared pool of configurablecomputing resources (e.g., networks, servers, storage, applications, andservices) that can be rapidly provisioned and released with minimalmanagement effort or service provider interaction. The cloud server canprovide services to organizations or other entities as:

(i) Software as a Service (SaaS)—The clients run the cloud server'sapplications on the cloud server's computing resources. The applicationsare accessible from various devices through either a thin clientinterface, such as a web browser (e.g., web-based email), or a programinterface. The client does not manage or control the underlying cloudcomputing infrastructure including network, servers, operating systems,storage, or even individual application capabilities, with the possibleexception of limited user-specific application configuration settings.

(ii) Platform as a Service (PaaS)—The clients can deploy their ownapplications onto the cloud server's computing resources. Theapplication can be acquired or created by the clients using programminglanguages, libraries, services, and tools supported by the cloud server.The client does not manage or control the underlying cloud server'scomputing resources including network, servers, operating systems, orstorage, but has control over the deployed applications and possiblyconfiguration settings for the application-hosting environment.

(iii) Infrastructure as a Service (IaaS)—The clients can provisionprocessing, storage, networks, and other fundamental computingresources. The clients can deploy and run arbitrary software, which caninclude operating systems and applications on the provisioned resources.The client does not manage or control the underlying cloud computinginfrastructure but has control over operating systems, storage, anddeployed applications; and possibly limited control of select networkingcomponents (e.g., host firewalls).

Virtual machines running on local data centers or cloud servers haveextensive data security requirements and typically need to becontinuously available to deliver services to clients. For disasterrecovery and avoidance, the computing service provider that providesvirtual machine capability needs to avoid data corruption and servicelapses to clients. Therefore, the computing service providerperiodically takes snapshots of the running virtual machines. A snapshotis a copy of the virtual machine's content at a given point in time.Snapshots can be used to restore a virtual machine to a particular pointin time when a failure or system error occurs. The computing serviceprovider can take multiple snapshots of a virtual machine to createmultiple possible point-in-time restore points. When a virtual machinereverts to a snapshot, current virtual machine's data volumes and memorystates are deleted, and the snapshot becomes the new parent snapshot forthat virtual machine.

Snapshots are intended to store the virtual machine data for as long asdeemed necessary to make it feasible to go back in time and restore whatwas lost. As the main objective of snapshots is long-term data storage,various data reduction techniques are typically used by a snapshotmanager in a computing service provider to reduce the snapshot size andfit the data into the smallest amount of disk space possible. Thisincludes skipping unnecessary swap data, data compression, and datadeduplication, which removes the duplicate blocks of data and replacesthem with references to the existing ones. Because snapshots arecompressed and duplicated to save storage space, they no longer looklike virtual machines and are often stored in a special format. Assnapshots just a set of files, the snapshot repository is a folder,which can be located anywhere: on a dedicated server, storage areanetwork (SAN) or dedicated storage in a computing service provider'sinfrastructure.

Modern-day clients tend to run hybrid workloads where multiple virtualmachines are running on a local data center and others on one or morecloud servers, which may be located remotely and/or may be leased fromthird party providers. An opportunity arises to keep a snapshot history,stored in sequence, and spanning multiple virtual machines on multiplecloud servers and local data centers at the clients' end. A furtheropportunity arises to configure scheduling of snapshot capture acrossmultiple systems, potentially remoted and potentially leased fromdifferent third party cloud server providers. A further opportunityarises to provide improved disaster recovery for virtual machinesexecuting on third party cloud servers in the event of data loss due tonatural disasters, man-made disasters such as acts of terrorism, and/orvirus attacks. A workload management system and a centralized workloadmanagement interface are needed to manage the backup and recovery forany running virtual machines, and browse and retrieve files in any ofthe running virtual machines across multiple cloud servers and the localdata center.

SUMMARY

A system and a method are provided that can be used for restoring avirtual machine or an instance with an Internet Protocol address, a rootvolume and one or more corrupted data volumes. As used herein, nodistinction is intended between a virtual machine and an instance. Thecorrupted virtual machine is hosted on a cloud server that hosts aplurality of virtual machines. The corrupted virtual machine isrecovered by launching a recovery virtual machine in the cloud server.The recovery virtual machine is instructed to launch one or more newdata volumes based upon captured file system images in one or moresnapshots taken of corrupted data volumes of the virtual machine priorto becoming corrupted. The recovery virtual machine is furtherinstructed to detach the corrupted data volumes, and attach the new datavolumes launched to the virtual machine. The Internet Protocol addressof the restored virtual machine remains unchanged.

Embodiments of the technology described herein, or elements thereof, canbe implemented in the form of a computer product including anon-transitory computer-readable storage medium with the computer usableprogram code for performing the method steps indicated. Furthermore,embodiments of the invention or elements thereof can be implemented inthe form of an apparatus including a memory and at least one processorthat is coupled to the memory and operative to perform exemplary methodsteps. Yet further, in another aspect, embodiments of the invention orelements thereof can be implemented in the form of means for carryingout one or more of the method steps described herein; the means caninclude (i) hardware module(s), (ii) software module(s) executing on oneor more hardware processors, or (iii) a combination of hardware andsoftware modules; any of (i)-(iii) implement the specific techniques setforth herein, and the software modules are stored in a computer-readablestorage medium (or multiple such media).

Thus, a technology is provided that enables clients running hybridworkloads with multiple virtual machines on local data centers andothers on one or more cloud servers the capability to protect and managetheir workloads in a platform-agnostic workload management system. Theworkload management system assigns protection policies for the virtualmachines running on multiple cloud servers and local data centers, keepssnapshot histories of each of the running virtual machines, and providesthe capability to search, restore and retrieve files in any of therunning virtual machines.

Embodiments advantageously employ the disclosed technology implement aworkload management system and centralized workload management interfaceto manage backup and recovery for any of a variety of virtual machines,and browse and retrieve files in any of the virtual machines acrossmultiple cloud servers and the local data center; thereby improvingfunctioning of a computer system enabling the computer system asimproved to run hybrid workloads where multiple virtual machines arerunning on a local data center and others on one or more cloud servers,which may be located remotely and/or may be leased from third partyproviders. Specifically, embodiments provide heretofore unavailableabilities to keep a snapshot history, stored in sequence, and spanningmultiple virtual machines on multiple cloud servers and local datacenters at the clients' end irrespective of whether machines or serversare owned, leased, local or remote. Such capability results in a vastimprovement in the ability of end users to manage their system withoutthe expense, delay of accessing individual machines at different sitesand operated by different people, making such widely distributedprocessing infrastructure available without requiring individuallylogins for each employee at each machine. Yet further, improved coverageof machine state of any machines in the infrastructure is provided byintegrating snapshots of any machines together under a common workloadmanagement interface.

A further improvement in functionality of the computer system arisesfrom the disclosed configuration of a scheduling mechanism for snapshotcapture across multiple systems, potentially remoted and potentiallyleased from different third party cloud server providers. Improvedquality of backups results from proper scheduling of snapshot takingacross the multiple computer systems. Such pan-infrastructure managementcapability, heretofore unknown, improves the usability of the computersystems and ability to coordinate backup and other tasks among thevarious computer systems.

A yet further improvement in functionality of the computer system arisesfrom the disclosed configuration of a common workload managementinterface that enables an operator to access the capabilities of anyvirtual machine, whether local, remote, owned or leased, in conjunctionwith viewing and accessing information for any other virtual machine inthe infrastructure of the end user. Swap data that is unnecessary tocapture in making a backup can be skipped. Operations can be controlledsuch as data compression and data deduplication, which removes theduplicate blocks of data and replaces them with references to theexisting ones. Backup snapshots that no longer look like virtualmachines are often stored in a special format, facilitating compressionand deduplication that saves storage space.

A still further improvement in functionality of the computer systemarises from centralized snapshot management techniques disclosed isimproved disaster recovery for virtual machines or instances executingon third party cloud servers in the event of data loss due to naturaldisasters, man-made disasters such as acts of terrorism, and/or virusattacks. Specifically, the heretofore unavailable techniques disclosedfor remotely deleting virtual volumes mounted to virtual machines thathave become corrupted and replace such volumes with un-corrupted datafrom a captured snapshot history enables virtual machines that have beeninfected by viruses, natural disasters, or human carelessness ormalfeasance to be recovered seamlessly, without the requirement ofchanging an Internet Protocol (IP) address of the virtual machine. Datacorruptions can be avoided, avoid data, service lapses to clients can bereduced, damage incurred from non-preventable disasters can be remediesmore quickly, and seamlessly than with heretofore known approaches.

These and other features, aspects, and advantages of the invention willbecome apparent from the following detailed description of illustrativeembodiments thereof, which is to be read in connection with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an architectural level schematic of an exampleenvironment that includes a workload management system that identifieshistorical snapshots for virtual machines across cloud servers and localdata centers, in accordance with an implementation.

FIG. 2 illustrates an architectural level schematic of an exampleenvironment that includes multiple workload management systems thatidentify historical snapshots for virtual machines across cloud serversand local data centers, in accordance with an implementation.

FIG. 3 illustrates an example of a cloud server.

FIG. 4 is a symbolic drawing indicating how the snapshot storagedatabase in FIG. 3 is organized.

FIG. 5 illustrates an example of a workload management system, accordingto an embodiment of the invention.

FIG. 6 is a sequence diagram illustrating a representative method ofprocessing new accounts in cloud servers by the workload managementsystem.

FIG. 7 shows an example dialog box for customizing a virtual machine'sservice level agreements.

FIG. 8 is a sequence diagram illustrating a representative method offinding content among incremental snapshots in virtual machines on oneor more cloud servers by the workload management system, according to anembodiment of the invention.

FIG. 9 illustrates an example of a first indexing virtual machine forfinding content among incremental snapshots in virtual machines on acloud server, according to an embodiment of the invention.

FIG. 10 illustrates an example UI screen for viewing the snapshots for aselected virtual machine, by calendar month.

FIG. 11 illustrates an example UI screen for viewing the snapshots for aselected virtual machine, by calendar day.

FIG. 12 illustrates an example UI screen for viewing the files inside asnapshot for a selected virtual machine.

FIG. 13 illustrates an example UI screen for selecting a particular fileinside a snapshot from a selected virtual machine for download.

FIG. 14 is a sequence diagram illustrating a representative method ofretrieving a selected file from virtual machines on a cloud server bythe workload management system, according to an embodiment of theinvention.

FIG. 15 is a sequence diagram illustrating a representative method ofrestoring a corrupted virtual machine on a cloud server by the workloadmanagement system, according to an embodiment of the invention.

FIGS. 16A, 16B, and 16C (hereafter FIG. 16) illustrate a recoveryvirtual machine restoring a corrupted virtual machine.

FIG. 17 is an example block diagram of a computing system that mayincorporate embodiments of the present invention.

DETAILED DESCRIPTION

The following description is presented to enable any person skilled inthe art to make and use the invention, and is provided in the context ofa particular application and its requirements. Various modifications tothe disclosed embodiments will be readily apparent to those skilled inthe art, and the general principles defined herein may be applied toother embodiments and applications without departing from the spirit andscope of the present invention. Thus, the present invention is notintended to be limited to the embodiments shown but is to be accordedthe widest scope consistent with the principles and features disclosedherein.

System Overview

FIG. 1 illustrates an architectural level schematic of an exampleenvironment that includes a workload management system (WMS) 122 thatidentifies historical snapshots for virtual machines across a pluralityof cloud servers and local data centers, in accordance with animplementation. Because FIG. 1 is an architectural diagram, certaindetails are intentionally omitted to improve the clarity of thedescription. The discussion of FIG. 1 will be organized as follows.First, the elements of the figure will be described, followed by theirinterconnections.

The system 100 includes a cloud server A 112, a cloud server B 114, acloud server C 116, workload management system clients (WMS clients) 106and 108, a local data center 110 hosting a workload management system122, and the network(s) 102. As used herein, a “WMS client” is a clientinterface application for the workload management system (WMS) 122. Forthe sake of clarity, only three cloud servers and two WMS clients areshown to be connected to the local data center 110 hosting the workloadmanagement system 122 through the network(s) 102. However, any number ofcloud servers and WMS clients can be connected to the local data center110 hosting the workload management system 122 through the network(s)102. The interconnection of the elements of system 100 will now bedescribed. Network(s) 102 couples the cloud server A 112, the cloudserver B 114, the cloud server C 116, the WMS clients 106 and 108, thelocal data center 110, all in communication with each other (indicatedby solid double-arrowed lines). In one embodiment, the workloadmanagement system 122 may be run using a dedicated hardware-basedappliance inside the local data center 110.

The actual communication path through the internet can be point-to-pointover public and/or private networks. The communications can occur over avariety of networks 102, e.g., private networks, VPN, MPLS circuit, orInternet, and can use appropriate application programming interfaces(APIs) and data interchange formats, e.g., Representational StateTransfer (REST), JavaScript™ Object Notation (JSON), Extensible MarkupLanguage (XML), Simple Object Access Protocol (SOAP), Java™ MessageService (JMS), and/or Java Platform Module System. All of thecommunications can be encrypted. The communication is generally over anetwork such as the LAN (local area network), WAN (wide area network),telephone network (Public Switched Telephone Network (PSTN), SessionInitiation Protocol (SIP), wireless network, point-to-point network,star network, token ring network, hub network, Internet, inclusive ofthe mobile Internet, via protocols such as EDGE, 3G, 4G LTE, Wi-Fi, andWiMAX. Additionally, a variety of authorization and authenticationtechniques, such as username/password, Open Authorization (OAuth),Kerberos, SecureID, digital certificates and more, can be used to securethe communications.

The WMS clients 106 and 108 provide an interface for managing theworkload management system 122 for administering services, includingbackup, instant recovery, replication, search, analytics, archival,compliance, and data management across the data local center 110 andcloud servers 112, 114, and 116. Users 124 running multiple virtualmachines on the cloud server A 112, the cloud server B 114, the cloudserver C 116, and the local data center 110 are connected to theworkload management system 122 through WMS clients 106 and 108. Eachclient has an account in at least one of the cloud servers and the localdata center. Examples of electronic devices which can deploy WMS clients106 and 108 include all varieties of computers, workstations, laptopcomputers, handheld computers, and smartphones. The WMS clients 106 and108 may provide a user interface (e.g., a web-based interface or agraphical user interface) that displays virtual machine backupinformation such as identifications of the virtual machines protectedand the historical versions or time machine views for each of thevirtual machines protected. A time machine view of a virtual machine mayinclude snapshots of the virtual machine over a plurality of points intime. Each snapshot may comprise the state of the virtual machine at aparticular point in time. Each snapshot may correspond to a differentversion of the virtual machine (e.g., Version 1 of a virtual machine maycorrespond to the state of the virtual machine at a first point in time,and Version 2 of the virtual machine may correspond to the state of thevirtual machine at a second point in time subsequent to the first pointin time).

Cloud servers in environment 100 may comprise a cloud computingenvironment providing Software-as-a-Service (SaaS), Product-as-a-Service(SaaS) or Infrastructure-as-a-Service (IaaS) services. Examples ofcommon cloud servers today include Amazon Web Services AWS™, DigitalOcean™, Microsoft Azure™, Rackspace Open Cloud™, Google Compute Engine™,HP Enterprise Converged Infrastructure™, IBM SmartCloud Enterprise™, IBMSmartCloud Enterprise™, CloudStack™, OpenStack™, Cisco CloudInfrastructure Solutions™, CenturyLink Cloud™, Netrepid™, Green CloudTechnologies™, Amazon VPC™, CloudStack™, Linode™ and so on. In thetechnology described herein, cloud server A 112, cloud server B 114 andcloud server C 116 can use any of the platforms described.

In addition to the workload management system 122, the local data center110 may include one or more virtualization managers, such as thevirtualization manager 120, in communication with one or more storagedevices, such as storage device 118. The one or more virtualizationmanagers may also be in communication with the workload managementsystem 122. The virtualization manager 120, storage device 118, andworkload management system 122 may be in communication with each othervia a networking fabric connecting servers and data storage units withinthe local data center to 110 each other. The workload management system122 may include a workload management system for backing up virtualmachines and/or files within a virtualized infrastructure. Thevirtualization manager 120 may be used to create and manage one or morevirtual machines associated with a virtualized infrastructure. The oneor more virtual machines may run various applications, such as adatabase application or a web server. The storage device 118 may includeone or more hardware storage devices for storing data, such as a harddisk drive (HDD), a magnetic tape drive, a solid-state drive (SSD), astorage area network (SAN) storage device, or a networked-attachedstorage (NAS) device. In some cases, a local data center, such as datacenter 110, may include thousands of servers and/or data storage devicesin communication with each other. The data storage devices may comprisea tiered data storage infrastructure (or a portion of a tiered datastorage infrastructure). The tiered data storage infrastructure mayallow for the movement of data across different tiers of a data storageinfrastructure between higher-cost, higher-performance storage devices(e.g., solid-state drives and hard disk drives) and relativelylower-cost, lower-performance storage devices (e.g., magnetic tapedrives).

The virtualization manager 120 may manage a virtualized infrastructureinside the local data center 110 and perform management operationsassociated with the virtualized infrastructure. The virtualizationmanager 120 may manage the provisioning of virtual machines runningwithin the virtualized infrastructure and provide an interface tocomputing devices interacting with the virtualized infrastructure in thelocal data center 110. In one example, the virtualization manager 120may set a virtual machine into a frozen state in response to a snapshotrequest made via an application programming interface (API) by theworkload management system 122. Setting the virtual machine into afrozen state may allow a point in time snapshot of the virtual machineto be stored or transferred. The virtualization manager 120 may thentransfer the snapshot of the virtual machine to a snapshot storage inresponse to a request made by the workload management system 122. Afterthe data associated with the point in time snapshot of the virtualmachine has been transferred to the snapshot storage the virtual machinemay be released from the frozen state (i.e., unfrozen). Thevirtualization manager 120 may perform various virtual machine relatedtasks, such as cloning virtual machines, creating new virtual machines,monitoring the state of virtual machines, moving virtual machinesbetween physical hosts for load balancing purposes, and facilitatingbackups of virtual machines.

In the embodiment illustrated in FIG. 1, the workload management system122 may include a workload management system for backing up virtualmachines in the local data center 110. The WMS clients 106 and 108assign protection policies for the virtual machines running for each ofthe cloud servers (cloud server A 112, cloud server B 114, and cloudserver C 116) and the local data center 110 through the workloadmanagement system 122. The workload management system 122 may furtherinclude the capability to finding content in snapshots captured fromvirtual machines running on multiple cloud servers connected to theworkload management system 122, include the snapshot content in ametadata file and forward the metadata file to the WMS clients 106 and108. The metadata file may include the name of a file, a size of thefile, file permissions associated with the file, when the file was lastmodified, and file mapping information associated with an identificationof the location of the file stored within the virtual machine. The WMSclients 106 and 108 keeps snapshot metadata histories of each of therunning virtual machines, provides the capability to search, restore andretrieve files in any of the running virtual machines through thesnapshot metadata received from the workload management system 122. TheWMS clients 106 and 108 may also request the workload management system122 to restore any corrupted virtual machine in any of the cloud serversin communication with the workload management system 122.

FIG. 2 illustrates an architectural level schematic of an environmentthat includes multiple workload management systems that identifyhistorical snapshots for virtual machines on multiple cloud servers andlocal data centers, in accordance with an implementation. In theembodiment illustrated in FIG. 2, the workload management system 122 maybe run from the cloud server (e.g., the software-level components may beinstalled on a cloud server). In addition to the workload managementsystem 122 being hosted in the local data center 110, each cloud server(cloud server A 112, cloud server B 114, and cloud server C 116) mayinclude a workload management system 122. The WMS clients 106 and 108assign protection policies for the virtual machines running for each ofthe cloud servers (cloud server A 112, cloud server B 114, and cloudserver C 116) and the local data center 110 through the cloud server'srespective workload management system. The workload management systems122 may further include the capability to find content in snapshotscaptured from virtual machines running on their servers, include thesnapshots content in a metadata file and forward the metadata file tothe WMS clients 106 and 108. The metadata file may include the name of afile, a size of the file, file permissions associated with the file,when the file was last modified, and file mapping information associatedwith an identification of the location of the file stored within thevirtual machine. The WMS clients 106 and 108 keeps snapshot metadatahistories of each of the running virtual machines, provides thecapability to search, restore and retrieve files in any of the runningvirtual machines through the snapshot metadata received from theworkload management system 122. The WMS clients 106 and 108 may alsorequest the workload management system 122 to restore any corruptedvirtual machine in any of the cloud servers through the cloud server'sworkload management system.

In one embodiment, the networked computing environments 100 and 200 mayinclude a virtualized infrastructure that provides software, dataprocessing, and/or data storage services to users 124 accessing theservices via the networked computing environment. In one example,networked computing environments 100 and 200 may provide cloud basedwork productivity or business related applications to computing devices.In some embodiments, networked computing environments 100 and 200 mayprovide remote access to secure applications and files stored within thelocal data center 110 and cloud servers 112, 114, and 116 from a remotecomputing device, such as the computing devices used by users 124.

Cloud Server

FIG. 3 illustrates a symbolic drawing of a cloud server. A client withan account in a cloud server may run one or more virtual machines on thecloud server's platform. Each running virtual machine has its ownInternet Protocol (IP) address. Each virtual machine has a root volumeand one or more data volumes. A volume is defined as virtual storage inthe virtual machine and is connected to the virtual machine. A rootvolume contains the operating system of the virtual machine. A rootvolume may be created when a virtual machine is initialized. When thevirtual machine is deleted, the root volume is also deleted. A datavolume is defined as the second or subsequent volume among thoseconnected to a virtual machine. The data volume does not contain anypart of the operating system of the virtual machine. A data volume canbe attached or detached to a virtual machine. A data volume of a firstvirtual machine can be detached from the first virtual machine andattached to a second virtual machine.

Referring to FIG. 3, a user is running a virtual machine X 310 with IPaddress XXX.XXX.XXX.XX1, virtual machine Y 318 with IP addressXXX.XXX.XXX.XX2, and virtual machine Z 324 with IP addressXXX.XXX.XXX.XX3 in the cloud server A 112. The virtual machine X 310with IP address XXX.XXX.XXX.XX1 has a root volume X1 312, a data volumeX2 314 and a data volume X3 316. The virtual machine Y 318 with IPaddress XXX.XXX.XXX.XX2 has a root volume Y1 320, and a data volume Y2322. The virtual machine Z 324 with IP address XXX.XXX.XXX.XX3 has aroot volume Z1 326, a data volume Z2 328, a data volume Z3 330 and adata volume Z4 332.

The cloud server A 112 may further include a snapshot manager 304 and asnapshot storage 306. The snapshot manager 304 may follow a backupschedule to capture snapshots of a virtual machine at a particular pointin time or one or more data volumes associated with the virtual machineat the particular point in time. In one example, the backup schedule isbased on the service level agreements (SLA) that prevails between theworkload management system 122 and the users 124. An SLA definesspecific aspects of the service, including how often to take virtualmachine snapshots and how long to keep the snapshots, as agreed betweenthe workload management system 122 and the users 124.

The snapshots captured by the snapshot manager 304 can be stored in adedicated storage, snapshot storage 306. The cloud server A 112 may alsoinclude a workload management system.

FIG. 4 is a symbolic drawing indicating how the snapshot storagedatabase 306 in FIG. 3 is organized, according to an embodiment of theinvention. In some embodiments, a directory for each virtual machineprotected using the snapshot manager 304 may be created (e.g., thedirectory for Virtual Machine X may be/snapshots_X). Snapshots and otherdata associated with a virtual machine may reside within the directoryfor the virtual machine. In one example, snapshots of a virtual machinemay be stored in subdirectories of the directory (e.g., a first snapshotof Virtual Machine X may reside in/snapshots_X/s1/and a second snapshotof Virtual Machine X may reside in/snapshots_X/s2/).

In some embodiments, a plurality of versions of a virtual machine may bestored as a base file associated with a complete image of the virtualmachine at a particular point in time (e.g., Version V1/Time T1 andVersion V4/Time T4) and one or more incremental files (also referred toas “incrementals”) (e.g., Version V2/Time T2; Version V3/Time T3; andVersion V5/Time T5) associated with forward and/or reverse incrementalchanges derived from the base file. An incremental file may comprise aforward incremental file or a reverse incremental file. A forwardincremental file may include a set of data representing changes thathave occurred since an earlier point in time snapshot of a virtualmachine. To generate a snapshot of the virtual machine corresponding toa forward incremental file, the forward incremental file may be combinedwith an earlier point in time snapshot of the virtual machine (e.g., theforward incremental file may be combined with the last full image of thevirtual machine that was captured before the forward incremental wascaptured and any other forward incremental files that were capturedsubsequent to the last full image and prior to the forward incrementalfile). A reverse incremental file may include a set of data representingchanges from a later point in time snapshot of a virtual machine. Togenerate a snapshot of the virtual machine corresponding to a reverseincremental file, the reverse incremental file may be combined with alater point in time snapshot of the virtual machine (e.g., the reverseincremental file may be combined with the most recent snapshot of thevirtual machine and any other reverse incremental files that werecaptured prior to the most recent snapshot and subsequent to the reverseincremental file).

In some embodiments, each version of the plurality of versions of avirtual machine may correspond to a merged file. A merged file mayinclude pointers or references to one or more files and/or one or morechunks associated with a particular version of a virtual machine. In oneexample, a merged file may include a first pointer or symbolic link to abase file and a second pointer or symbolic link to an incremental fileassociated with the particular version of the virtual machine. In someembodiments, the one or more incremental files may correspond withforward incrementals, reverse incrementals, or a combination of bothforward incrementals and reverse incrementals.

Referring to FIG. 4, a set of virtual machine snapshots stored forvirtual machine X 310 includes a first set of files in the snapshotstorage 306. As depicted, the first set of files includes a set a fullimage (Base 1) for snapshot V1 captured at time T1, and a set of forwardincrementals (F1 for snapshot version V2 captured at time T2, F2 forsnapshot version V3 captured at time T3). The first set of files alsoincludes another full image (Base 2) for snapshot V4 captured at timeT4, and a forward incremental (F3) for snapshot version V5 captured attime T5. In some cases, the file size of the forward incrementals mayboth be less than the file size of the base image. The base imagecorresponding to version V1 and V4 of virtual machine X may comprisefull images of Virtual Machine X at a times T1 and T4 respectively. Thebase image may include the content of the data volume X2 314 and thedata volume 316 of the Virtual Machine X 310 at times T1 and T4.

Workload Management System

FIG. 5 illustrates an example of a workload management system 122. Inone embodiment, the workload management system 122 may manage theextraction and storage of virtual machine snapshots captured atdifferent time points of one or more virtual machines running in thevirtualization manager 120 within the local data center 110. In oneembodiment, the workload management system 122 may manage the snapshotcapturing schedule of one or more virtual machines running on one ormore cloud servers. In one embodiment, the workload management system122 may manage the extraction and storage of virtual machine snapshotscaptured at different time points of one or more virtual machinesrunning in the virtualization manager 120 within the local data center110 and the snapshot capturing schedule of one or more virtual machinesrunning on one or more cloud servers. In response to a restore orrecover command from a WMS client, the workload management system 122may restore a point in time version of a virtual machine or restorepoint in time versions of one or more files located on the virtualmachine.

Referring to FIG. 5, the workload management system 122 may have severalsoftware-level components. The software-level components of the workloadmanagement system 122 may include a cloud data manager 542, an SLApolicy engine 552, a data management system 554, a distributed jobscheduler 556, a distributed metadata store 560, and a distributed filesystem 558. In one embodiment, the software-level components of theworkload management system 122 may be run using a dedicatedhardware-based appliance with one or more processors and memory system.In another embodiment, the software-level components of the workloadmanagement system 122 may be run from the cloud (e.g., thesoftware-level components may be installed on a cloud server'splatform).

The SLA policy engine 552 includes intelligence to determine thesnapshot capturing schedule to meet terms of service level agreementsbetween the workload management system 122 and the users 124, withspecific aspects of the service, including how often to take virtualmachine snapshots and how long to keep the snapshots, as agreed betweenthe workload management system 122 and the users 124.

The distributed file system 558 may present itself as a single filesystem in the workload management system 122 and is shared by one ormore physical machines connected to the workload management system 122.Each file stored in the distributed file system 558 may be partitionedinto one or more chunks. Each of the one or more chunks may be storedwithin the distributed file system 558 as a separate file. The filesstored within the distributed file system 558 may be replicated ormirrored over a plurality of physical machines, thereby creating aload-balanced and fault-tolerant distributed file system. In oneexample, workload management system 122 may include ten physicalmachines and a first file corresponding with a snapshot of a virtualmachine (e.g., /snapshots_A/s1/s1.full) may be replicated and stored onthree of the ten machines.

The distributed metadata store 560 may include a distributed databasemanagement system that provides high availability without a single pointof failure. In one embodiment, the distributed metadata store 560 maycomprise a database, such as a distributed document-oriented database.The distributed metadata store 560 may be used as a distributedkey-value storage system. In one example, the distributed metadata store560 may comprise a distributed NoSQL key-value store database. In somecases, the distributed metadata store 560 may include a partitioned rowstore, in which rows are organized into tables or other collections ofrelated data held within a structured format within the key-value storedatabase. A table (or a set of tables) may be used to store metadatainformation associated with one or more files stored within thedistributed file system 560. In one embodiment, a new file correspondingwith a snapshot of a virtual machine may be stored within thedistributed file system 558 and metadata associated with the new filemay be stored within the distributed metadata store 560.

In some cases, the distributed metadata store 560 may be used to manageone or more versions of a virtual machine. Each version of the virtualmachine may correspond with a full image snapshot of the virtual machinestored within the distributed file system 558 or an incremental snapshotof the virtual machine (e.g., a forward incremental or reverseincremental) stored within the distributed file system 558. In oneembodiment, the one or more versions of the virtual machine maycorrespond to a plurality of files. The plurality of files may include asingle full image snapshot of the virtual machine and one or moreincrementals derived from the single full image snapshot. The singlefull image snapshot of the virtual machine may be stored using a firststorage device of a first type (e.g., an HDD) and the one or moreincrementals derived from the single full image snapshot may be storedusing a second storage device of a second type (e.g., an SSD). In thiscase, only a single full image needs to be stored, and each version ofthe virtual machine may be generated from the single full image or thesingle full image combined with a subset of the one or moreincrementals. Furthermore, each version of the virtual machine may begenerated by performing a sequential read from the first storage device(e.g., reading a single file from a HDD) to acquire the full image and,in parallel, performing one or more reads from the second storage device(e.g., performing fast random reads from an SSD) to acquire the one ormore incrementals.

The distributed job scheduler 556 may be used for scheduling backup jobsthat acquire and store virtual machine snapshots for one or more virtualmachines in the local data centers and the cloud servers over time. Thedistributed job scheduler 556 may follow a backup schedule to backup anentire image of a virtual machine at a particular point in time or oneor more data volumes associated with the virtual machine at theparticular point in time. In one example, the backup schedule is the SLAagreement that prevails between the workload management system 122 andthe users 124. Each of the one or more tasks associated with a job maybe run on a particular processor of the workload management system 122.

The distributed job scheduler 556 may comprise a distributed faulttolerant job scheduler, in which jobs affected by processor failures arerecovered and rescheduled to be run on available processors. Thedistributed job scheduler 556 may run job scheduling processes on eachprocessor in a workload management system 122 or on a plurality ofprocessors in the workload management system 122. In one example, thedistributed job scheduler 556 may run a first set of job schedulingprocesses on a first processor in the workload management system 122, asecond set of job scheduling processes on a second processor in theworkload management system 122, and a third set of job schedulingprocesses on a third processor in the workload management system 122.The first set of job scheduling processes, the second set of jobscheduling processes, and the third set of job scheduling processes maystore information regarding jobs, schedules, and the states of jobsusing a metadata store, such as distributed metadata store 560. In theevent that the first processor running the first set of job schedulingprocesses fails (e.g., due to a network failure or a physical machinefailure), the states of the jobs managed by the first set of jobscheduling processes may fail to be updated within a threshold period oftime (e.g., a job may fail to be completed within 30 seconds or within 3minutes from being started). In response to detecting jobs that havefailed to be updated within the threshold period of time, thedistributed job scheduler 556 may undo and restart the failed jobs onavailable processors within the workload management system 122.

The cloud snapshot metadata manager 542 may have the capability tofinding content in snapshots captured from virtual machines running onmultiple cloud servers, compile a metadata file for the contents in thesnapshots and forward the metadata file to the WMS clients 106 and 108.The cloud snapshot metadata manager 542 may request data associated withvirtual blocks stored on a data volumes of the virtual machine that havechanged since a last snapshot of the virtual machine was taken or sincea specified prior point in time. Therefore, in some cases, if a snapshotof a virtual machine is the first snapshot taken of the virtual machine,then a full image of the virtual machine may be compiled to make ametadata file. However, if the snapshot of the virtual machine is notthe first snapshot taken of the virtual machine, then only the datablocks of the virtual machine that have changed since a prior snapshotwas may be compiled to make a metadata file.

The data management system 554 may comprise an application running onthe workload management system 122 that manages and stores one or moresnapshots of a virtual machine in the local data center 110. In oneexample, the data management system 554 may comprise a highest levellayer in an integrated software stack running on the workload managementsystem 122. The integrated software stack may include the datamanagement system 554, the distributed job scheduler 556, thedistributed metadata store 560, and the distributed file system 558. Insome cases, the integrated software stack may run on other computingdevices, such as a server or computing device. The local workloadmanagement system 554 may use the distributed job scheduler 556, thedistributed metadata store 560, and the distributed file system 558 tomanage and store one or more snapshots of a virtual machine in the localdata center 110. Each snapshot of the virtual machine may correspond toa point in time version of the virtual machine. The local workloadmanagement system 554 may generate and manage a list of versions for thevirtual machine. Each version of the virtual machine may map to orreference one or more chunks and/or one or more files stored within thedistributed file system 558. Combined together, the one or more chunksand/or the one or more files stored within the distributed file system558 may comprise a full image of the version of the virtual machine.

Sign Up Process for Workload Management System

FIG. 6 is an example workflow 600 illustrating a representative methodprocessing new accounts in cloud server A 112 and cloud server B 114 bythe workload management system 122. In some embodiments, the actions inthe workflow may be performed in different orders and with different,fewer or additional actions than those illustrated in FIG. 6. Multipleactions can be combined in some implementations.

FIG. 6 includes workflow 600 that begins at step S6.1 when a userrequests through WMS client 106 to add account information for cloudserver A 112. The account information provided by the user may includecredentials required to access the account in the cloud server A 112.

Workflow 600 continues at step S6.2 when the user provides SLAinformation for the virtual machines the user is running on cloud serverA 112 through the WMS client 106. The SLA is recorded in SLA policyengine 552 in the workload management system 122.

At step S6.3, the SLA policy engine 552 connects to snapshot manager 306on cloud server A 112 to update the SLA for the virtual machines theuser is running on the cloud server A 112.

At step S6.4, the user requests through the WMS client 106 to addaccount information for the cloud server B 114. The account informationprovided by the user may include credentials required to access theaccount in the cloud server B 114.

At step S6.5, the user provides SLA information for the virtual machinesthe user is running on cloud server B 114 through the WMS client 106.The SLA is recorded in SLA policy engine 552 in the workload managementsystem 122.

At step S6.6, the SLA policy engine 552 connects to snapshot manager 606on the cloud server B 114 to update the SLA for the virtual machines theuser is running in the cloud server B 114.

FIG. 7 shows an example dialog box 700 for customizing a virtualmachine's service level agreements within the user interface of the WMSclient 106. The SLA includes specific aspects of the service, includinghow often to take virtual machine snapshots and how long to keep thesnapshots, as agreed between the workload management system 122 and theuser. In the example shown, a virtual machine snapshot is to be takenonce every four hours 734, once every day 744, once every month 754 andonce every year 764. The four-hour snapshots are to be kept for threedays 748, the daily snapshots are to be retained for thirty days 758,the monthly snapshots are kept for one month 768, and the yearlysnapshots are to be retained for two years 778. Note that the first fullsnapshot is to be taken at the first opportunity 774.

File Browsing and Searching

FIG. 8 is an example workflow 800 illustrating a representative methodof finding content among incremental snapshots in virtual machines oncloud server A 112 and cloud server B 114 by the workload managementsystem 122. In some embodiments, the actions in the workflow may beperformed in different orders and with different, fewer or additionalactions than those illustrated in FIG. 8. Multiple actions can becombined in some implementations.

FIG. 8 includes workflow 800 that begins at step S8.1, a user requeststhrough the WMS client 106 to update content for all the virtualmachines running on cloud server A 112 and cloud server B 114 to thecloud snapshot metadata manager 542 in the workload management system122.

Workflow 800 continues at step S8.2 when the cloud snapshot metadatamanager 542 instantiates a first indexing virtual machine 806 on thecloud server A 112.

At step S8.3, the first indexing virtual machine 806 compiles themetadata for available snapshots for virtual machines running on thecloud server A 112. As used herein, “available snapshots” may includeany snapshots that have not been previously compiled by an indexingvirtual machine to create a metadata file.

At step S8.4, the cloud snapshot metadata manager 542 instantiates asecond indexing virtual machine 808 on the cloud server B 114.

At step S8.5, the second indexing virtual machine 808 compiles themetadata for available snapshots for the virtual machines running on thecloud server B 114.

At step S8.6, the first indexing virtual machine 806 transmits thecompiled metadata for available snapshots for the virtual machinesrunning on the cloud server A 112 to the cloud snapshot metadata manager542.

At step S8.7, the second indexing virtual machine 808 transmits thecompiled metadata for available snapshots for the virtual machinesrunning on the cloud server B 114 to the cloud snapshot metadata manager542.

At step S8.8, the cloud snapshot metadata manager 542 forwards thecompiled metadata from the cloud server A 112 and the cloud server B 114to the WMS client 106.

At step S8.9, the WMS client 106 creates an index for the compiledmetadata from the cloud server A 112 and the cloud server B 114.

At step S8.10, the WMS client 106 presents the index of compiledmetadata to the user.

For the sake of clarity, the workflow 800 illustrates the cloud snapshotmetadata manager 542 accessing only two cloud servers. However, thecloud snapshot metadata manager 542 can access any number of cloudservers. In one embodiment, the first indexing virtual machine 806 andthe second indexing virtual machine 808 may be shut down aftertransmitting the compiled metadata to the cloud snapshot metadatamanager 542.

The index of compiled metadata may include a list of files that havebeen stored on a virtual machine and a version history for each of thefiles in the list. Each version of a file may be mapped to the earliestpoint in time snapshot of the virtual machine that includes the versionof the file or to a snapshot of the virtual machine that include theversion of the file (e.g., the latest point in time snapshot of thevirtual machine that includes the version of the file). In one example,the index of compiled metadata may be used to identify a version of thevirtual machine that includes a particular version of a file (e.g., aparticular version of a database, a spreadsheet, or a word processingdocument). In some cases, each of the virtual machines that are backedup or protected using workload management system 122 may have acorresponding virtual machine search index.

In some cases, if a virtual machine includes a plurality of datavolumes, then a virtual machine metadata may be generated for each datavolumes of the plurality of data volumes. For example, a first virtualmachine search metadata may catalog and map files located on a firstdata volume of the plurality of data volumes and a second virtualmachine search metadata may catalog and map files located on a seconddata volume of the plurality of data volumes. In this case, a globalmetadata for the virtual machine may include the first virtual machinesearch metadata and the second virtual machine search metadata.

In one embodiment, as each snapshot of a virtual machine is ingested,each data volume associated with the virtual machine is parsed in orderto identify a file system type associated with the data volume and toextract metadata (e.g., file system metadata) for each file stored onthe data volume. The metadata may include information for locating andretrieving each file from the data volume. The metadata may also includea name of a file, the size of the file, the last time at which the filewas modified, and a content checksum for the file. Each file that hasbeen added, deleted, or modified since a previous snapshot was capturedmay be determined using the metadata (e.g., by comparing the time atwhich a file was last modified with a time associated with the previoussnapshot). Thus, for every file that has existed within any of thesnapshots of the virtual machine, a virtual machine metadata may be usedto identify when the file was first created (e.g., corresponding to afirst version of the file) and at what times the file was modified(e.g., corresponding to subsequent versions of the file). Each versionof the file may be mapped to a particular version of the virtual machinethat stores that version of the file.

FIG. 9 illustrates an example of a first indexing virtual machine 902instantiated by the cloud snapshot metadata manager 542 for findingcontent among incremental snapshots in virtual machines on the cloudserver A 112. The first indexing virtual machine 902 with IP addressXXX.XXX.XXX.XX5 has a root volume 904. The first indexing virtualmachine 902 accesses the latest snapshot version for the virtual machineX 310 stored in the snapshot storage 306. As the virtual machine X 310has the data volume X2 314 and the data volume X3 316, the latestversion of the snapshot for virtual machine X 310 will have the contentfor both the data volume X2 314 and the data volume X3 316. In someembodiments, the last version of snapshot may be a forward incrementalfile that may be combined with an earlier point in time snapshot of thevirtual machine (e.g., the forward incremental file may be combined withthe last full image of the virtual machine that was captured before theforward incremental was captured and any other forward incremental filesthat were captured subsequent to the last full image and prior to theforward incremental file). In some embodiments, the last version ofsnapshot may be a reverse incremental file that may need be combinedwith a later point in time snapshot of the virtual machine (e.g., thereverse incremental file may be combined with the most recent snapshotof the virtual machine and any other reverse incremental files that werecaptured prior to the most recent snapshot and subsequent to the reverseincremental file). In some embodiments, the latest version of thesnapshot may be a full image.

The last set of virtual machine snapshots stored for virtual machine X310 in the snapshot storage 306 is the forward incremental (F3) forsnapshot version V5 captured at time T5. The forward incremental (F3)needs to be combined with the full image (Base 2) for snapshot V4captured at time T4. The combined snapshot is loaded into the two datavolumes of the first indexing virtual machine 902. The data volume X2906 of the first indexing virtual machine 902 will be a clone of datavolume X2 314 of the virtual machine X 310. The data volume X3 908 ofthe first indexing virtual machine 902 will be a clone of data volume X3316 of the virtual machine X 310. The first indexing virtual machine 902will compile a metadata for the content of the virtual machine X 310 byindexing the contents in the data volume X2 906 and the data volume X3908 of the first indexing virtual machine 902. The indexing may beperformed by an indexing application present in the first indexingvirtual machine 902. After the metadata is compiled, it is transmittedto the cloud snapshot metadata manager 542. The cloud snapshot metadatamanager 542 forwards the compiled metadata for the virtual machine X 310from the cloud server A 112 to the WMS client 106. The WMS client 106creates an index for the compiled metadata from the cloud server A 112and presents the index of compiled metadata to the client. In oneembodiment, generating an index can include building a tree like datastructure from discovered file metadata. Further detailed description ofgenerating an index, reference may be had to a commonly owned U.S.Nonprovisional patent application Ser. No. 14/628,019 entitled“Converged Search and Archival System,” by Arvind Jain et al., filedFeb. 20, 2015, which is incorporated by reference herein. Other typesand formats of indexes may be built in various embodiments withoutdeparting from the scope of the presently disclosed technology.

FIG. 10 illustrates an example UI screen 1000 of the WMS client 106 forviewing the snapshots for a selected virtual machine, by calendar month1002, with a dot on every date 1010 that has a stored snapshot. FIG. 11illustrates an example UI screen 1100 of the WMS client 106 for viewingthe snapshots for a selected virtual machine, by calendar day 1108.Contents of snapshots captured on Oct. 23, 2017 1104 at 12:41 AM 1110,1:41 AM 1112, 2:41 AM 1114, 3:41 AM 1116, 4:41 AM 1118, 5:41 AM 1120 and6:41 AM 1122 can be selected from UI screen 1100. A file can also besearched by name 1102. FIG. 12 illustrates an example UI screen 1200 forviewing the content 1206 inside a selected snapshot 1202 for a selectedvirtual machine 1204.

File Restore and Retrieval

The WMS client 106 may also receive an instruction from a user torestore a particular version of a particular file (e.g., a wordprocessing document or a database file), determine a second version fromthe plurality of time versions of the virtual machine that includes theparticular version of the particular file, extract the particularversion of the particular file from a portion of the second version ofthe virtual machine (e.g., extracting the particular version of theparticular file without completely generating the full image of thesecond version of the virtual machine), and output the particularversion of the particular file (e.g., by transferring the particularversion of the particular file to a server). In some cases, a group ofone or more files (e.g., associated with a file folder) may be restoredwithout requiring a full image of a virtual machine to be generated orrestored.

The WMS client 106 may also receive an instruction from the client toselect a particular version of a file to be retrieved from a selectedvirtual machine. FIG. 13 illustrates an example UI screen 1300 forselecting a particular file 1302 inside a snapshot for a selectedvirtual machine for download.

FIG. 14 is an example workflow 1400 illustrating a representative methodof retrieving a selected file in virtual machines on cloud server A 112by the workload management system 122 in FIG. 3. In some embodiments,the actions in the workflow may be performed in different orders andwith different, fewer or additional actions than those illustrated inFIG. 14. Multiple actions can be combined in some implementations.

FIG. 14 includes workflow 1400 that begins at step S14.1 when a userrequests through the WMS client 106 to retrieve a file from a selectedsnapshot of virtual machine X 310 on the cloud server A 112. The requestis sent to the cloud snapshot metadata manager 342 in the workloadmanagement system 122.

Workflow 1400 continues at step S14.2 when the cloud snapshot metadatamanager 542 instantiates a first indexing virtual machine 1402 on thecloud server A 112.

At step S14.3, the first indexing virtual machine 1402 retrieves therequested file. The file retrieval may be done by the first indexingvirtual machine 1402 mounting the selected snapshot of virtual machine X310 and accessing the file after the selected snapshot has been mountedto first indexing virtual machine's data volumes.

At step S14.4, the first indexing virtual machine 1402 transmits therequested file to the cloud snapshot metadata manager 542 in theworkload management system 122.

At step S14.5, the cloud snapshot metadata manager 542 forwards therequested file to the WMS client 106.

In-Place Virtual Machine Restore

In-place virtual machine or instance restore refers to the process wherea virtual machine needs to be terminated, and a new virtual machinelaunched from the old virtual machine's snapshots would replace the oldvirtual machine. A virtual machine may need to be terminated when itbecomes corrupted. A virtual machine may become corrupted for one ormore of the following reasons: damage in the root volume, damage in oneor more data volumes, the virtual machine was improperly shut down andso on. In one embodiment, the new virtual machine launched in the placeof the old virtual machine may have the same IP address as the oldvirtual machine.

In one embodiment, the snapshot storage 306 may manage and store aplurality of point in time versions of a virtual machine. The WMS client106 receives an instruction from a user to restore a certain virtualmachine by mounting a particular version of a snapshot in the selectedvirtual machine. In one embodiment, the workload management system 122may restore only the corrupted data volumes while leaving theuncorrupted data volumes intact. In one embodiment, the workloadmanagement system 122 may restore all the data volumes, including thecorrupted data volumes and the uncorrupted data volumes. In oneembodiment, the cloud server hosting the virtual machine with corrupteddata volumes may acknowledge the restoring process of one or more datavolumes of the virtual machine.

FIG. 15 is an example workflow 1500 illustrating a representative methodof restoring a virtual machine on the cloud server A 112 by the workloadmanagement system 122. In some embodiments, the actions in the workflowmay be performed in different orders and with different, fewer oradditional actions than those illustrated in FIG. 15. Multiple actionscan be combined in some implementations.

FIG. 15 includes workflow 1500 that begins at step S15.1 when a clientrequests through the WMS client 106 to restore the virtual machine X 310on the cloud server A 112. The request is sent to the cloud snapshotmetadata manager 542 in the workload management system 122.

Workflow 1500 continues at step S15.2 when the cloud snapshot metadatamanager 342 instantiates a recovery virtual machine 1502 on the cloudserver A 112.

At step S15.3, the recovery virtual machine 1502 mounts a snapshot ofthe virtual machine X 310 into its own data volumes. In one embodiment,the mounted snapshot may be selected by the user. In another embodiment,the mounted snapshot may be the last saved snapshot. In one embodiment,the mounted snapshot may contain data for the corrupted data volumes. Inanother embodiment, the mounted snapshot may contain data for all thedata volumes.

At step S15.4, the recovery virtual machine 1502 shuts down the virtualmachine X 310.

At step S15.5, the recovery virtual machine 1502 detaches the damageddata volumes from the virtual machine X 310. In one embodiment, therecovery virtual machine 1502 may detach one or more corrupted datavolumes, while keeping the uncorrupted volumes intact. In anotherembodiment, the recovery virtual machine 1502 may detach all the datavolumes.

At step S15.6, the recovery virtual machine 1502 detaches its own datavolumes and attaches the detached data volumes to the virtual machine X310. In one embodiment, the recovery virtual machine 1502 may alsocreate a new root volume for the virtual machine X 310. In oneembodiment, a root volume is created from an operating system image. Inanother embodiment, a root volume is created by mounting a snapshotcontaining an image of a previous version a root volume of the virtualmachine X 310. In one embodiment, data volumes which were mounted fromsnapshots are restored, while rest of the data volumes of the virtualmachine remain intact. In one embodiment, both the corrupted datavolumes and the uncorrupted data volumes are restored.

At step S15.7, the recovery virtual machine 1502 starts the virtualmachine X 310 with restored data volumes and root volume.

FIG. 16A illustrates an example of a recovery virtual machine 1602instantiated by the cloud snapshot metadata manager 542 for restoringthe virtual machine X 310 on the cloud server A 112. The data volume X2314 and the data volume X3 316 of the virtual machine X 310 arecorrupted. The recovery virtual machine 1602 with IP addressXXX.XXX.XXX.XX6 has a root volume 1604. In one embodiment, the user mayselect a snapshot to be mounted to the virtual machine X 310. In anotherembodiment, the recovery virtual machine 1602 accesses the latestsnapshot version for virtual machine X 310 stored in the snapshotstorage 306. In some embodiments, the last version of snapshot may be aforward incremental file that may be combined with an earlier point intime snapshot of the virtual machine (e.g., the forward incremental filemay be combined with the last full image of the virtual machine that wascaptured before the forward incremental was captured and any otherforward incremental files that were captured subsequent to the last fullimage and prior to the forward incremental file). In some embodiments,the last version of snapshot may be a reverse incremental file that mayneed be combined with a later point in time snapshot of the virtualmachine (e.g., the reverse incremental file may be combined with themost recent snapshot of the virtual machine and any other reverseincremental files that were captured prior to the most recent snapshotand subsequent to the reverse incremental file). In some embodiments,the latest version of the snapshot may be a full image.

Referring to FIG. 4, the last set of virtual machine snapshots storedfor the virtual machine X 310 in the snapshot storage 306 is a fullimage (Base 2) for snapshot V4 captured at time T4, and a forwardincremental (F3) for snapshot version V5 captured at time T5. Theforward incremental F3 is combined with the full image, and the combinedsnapshot is loaded into the two data volumes of the recovery virtualmachine 1602.

FIG. 16B illustrates the recovery virtual machine 1602 detaching thedamaged data volume X2 314 and data volume X3 316 from the virtualmachine X 310. FIG. 16C illustrates the recovery virtual machine 1602restoring the virtual machine X 310 by detaching its own data volumes,data volume X2 1606 and data volume X3 1608, and attaching the detacheddata volumes to the virtual machine X 310. The recovery virtual machine1602 may also create a new root volume X1 1610 for the virtual machine X310.

Computer System

FIG. 17 is an example block diagram of a computing system that mayincorporate embodiments of the present invention. System 1700 can beimplemented using a computer program stored in system memory, or storedon other memory and distributed as an article of manufacture, separatelyfrom the computer system. Particularly it can be used to implement theworkload management system 122 in various embodiments.

Computer system 1710 typically includes a processor subsystem 1772 whichcommunicates with a number of peripheral devices via bus subsystem 1750.These peripheral devices may include a storage subsystem 1726,comprising a memory subsystem 1722 and a file storage subsystem 1736,user interface input devices 1738, user interface output devices 1778,and a network interface subsystem 1776. The input and output devicesallow user interaction with computer system 1710 and network and channelemulators. Network interface subsystem 1774 provides an interface tooutside networks and devices of the system 1700. The computer systemfurther includes communication network 1784 that can be used tocommunicate with user equipment (UE) units; for example, as a deviceunder test.

The physical hardware component of network interfaces are sometimesreferred to as network interface cards (NICs), although they need not bein the form of cards: for instance they could be in the form ofintegrated circuits (ICs) and connectors fitted directly onto amotherboard, or in the form of microcells fabricated on a singleintegrated circuit chip with other components of the computer system.

User interface input devices 1738 may include a keyboard, pointingdevices such as a mouse, trackball, touchpad, or graphics tablet, ascanner, a touchscreen incorporated into the display, audio inputdevices such as voice recognition systems, microphones, and other typesof input devices. In general, use of the term “input device” is intendedto include all possible types of devices and ways to input informationinto computer system 1710.

User interface output devices 1778 may include a display subsystem, aprinter, a fax machine, or non-visual displays such as audio outputdevices. The display subsystem may include a flat panel device such as aliquid crystal display (LCD) or LED device, a projection device, acathode ray tube (CRT) or some other mechanism for creating a visibleimage. The display subsystem may also provide a nonvisual display suchas via audio output devices. In general, use of the term “output device”is intended to include all possible types of devices and ways to outputinformation from computer system 1710 to the user or to another machineor computer system. The computer system further can include userinterface output devices 1778 for communication with user equipment.

Storage subsystem 1726 stores the basic programming and data constructsthat provide the functionality of certain embodiments of the presentinvention. For example, the various modules implementing thefunctionality of certain embodiments of the invention may be stored in astorage subsystem 1726. These software modules are generally executed byprocessor subsystem 1772.

Storage subsystem 1726 typically includes a number of memories includinga main random access memory (RAM) 1734 for storage of instructions anddata during program execution and a read-only memory (ROM) 1732 in whichfixed instructions are stored. File storage subsystem 1736 providespersistent storage for program and data files, and may include a harddisk drive, a floppy disk drive along with associated removable media, aCD ROM drive, an optical drive, or removable media cartridges. Thedatabases and modules implementing the functionality of certainembodiments of the invention may have been provided on acomputer-readable medium such as one or more CD-ROMs, and may be storedby file storage subsystem 1736. The host memory storage subsystem 1726contains, among other things, computer instructions which, when executedby the processor subsystem 1772, cause the computer system to operate orperform functions as described herein. As used herein, processes andsoftware that are said to run in or on “the host” or “the computer,”execute on the processor subsystem 1772 in response to computerinstructions and data in the host memory storage subsystem 1726including any other local or remote storage for such instructions anddata.

Bus subsystem 1750 provides a mechanism for letting the variouscomponents and subsystems of computer system 1710 communicate with eachother as intended. Although bus subsystem 1750 is shown schematically asa single bus, alternative embodiments of the bus subsystem may usemultiple busses.

Computer system 1710 itself can be of varying types including a personalcomputer, a portable computer, a workstation, a computer terminal, anetwork computer, a television, a mainframe, or any other dataprocessing system or user device. Due to the ever changing nature ofcomputers and networks, the description of computer system 1710 depictedin FIG. 17 is intended only as a specific example for purposes ofillustrating embodiments of the present invention. Many otherconfigurations of computer system 1710 are possible having more or lesscomponents than the computer system depicted in FIG. 17.

In one embodiment, the workload management system 122 hosted in thelocal data center 112 may include four computer systems. Each of thefour computer systems may include a multi-core CPU, 64 GB of RAM, a 400GB SSD, three 4 TB HDDs, and a network interface controller. In thiscase, the four computer systems may be in communication with the one ormore networks 102 via the four network interface controllers. The fourcomputer systems may comprise four nodes of a server cluster. The servercluster may comprise a set of four computer systems that are connectedtogether via a network. The server cluster may be used for storing dataassociated with a plurality of virtual machines, such as backup dataassociated with a different point in time versions of 1000 virtualmachines.

Some Particular Implementations

Some particular implementations and features are described in thefollowing discussion.

One implementation of the disclosed technology includes a method of forrecovering a first virtual machine with an Internet Protocol address, afirst root volume and one or more data volumes that are corrupted. Thefirst virtual machine is hosted by a first cloud server that hostsplurality of virtual machines. The disclosed method includes: (i)instructing the first cloud server to launch a recovery virtual machine;(ii) instructing the recovery virtual machine to launch one or more newdata volumes based upon captured file system images in one or moresnapshots taken of corrupted data volumes of the first virtual machineprior to becoming corrupted; (ii) instructing the recovery virtualmachine to detach one or more corrupted data volumes; and (ii)instructing the recovery virtual machine to attach one or more new datavolumes launched to the first virtual machine.

In some implementations, the method further includes that the InternetProtocol address of the first virtual machine remains unchanged.

In some implementations, the method further includes halting the firstvirtual machine prior detaching corrupted data volumes.

In some implementations, the method further includes restarting thefirst virtual machine after attaching new data volumes.

In some implementations, the method further includes instructing therecovery virtual machine to launch a new root volume based upon capturedfile system images in one or more snapshots taken of corrupted datavolumes of the first virtual machine prior to becoming corrupted.

In some implementations, the method further includes instructing therecovery virtual machine to detach the first root volume.

In some implementations, the method further includes instructing therecovery virtual machine to attach the new root volume launched to thefirst virtual machine.

These methods and other implementations of the technology disclosed caninclude one or more of the following features and/or features describedin connection with additional methods disclosed. In the interest ofconciseness, the combinations of features disclosed in this applicationare not individually enumerated and are not repeated with each base setof features.

Another implementation may include a system, including one or moreprocessors and memory coupled to the processors, containing computerinstructions that, when executed on the processors, cause the system tofind content in one or more virtual machines on one or more cloudservers according to any of the methods described earlier.

Yet another implementation may include a non-transitorycomputer-readable storage media storing instructions to find content inone or more virtual machines on one or more cloud servers, whichinstructions, when combined with computer hardware and executed, cause acomputer to implement any of the methods described earlier. For purposesof this application, a computer-readable media does not include atransitory wave form.

While the technology disclosed is disclosed by reference to thepreferred embodiments and examples detailed above, it is to beunderstood that these examples are intended in an illustrative ratherthan in a limiting sense. It is contemplated that modifications andcombinations will readily occur to those skilled in the art, whichmodifications and combinations will be within the spirit of theinnovation and the scope of the following claims.

We claim as follows:
 1. A system for recovering a first virtual machinewith an Internet Protocol address, a first root volume and one or moredata volumes that are corrupted; wherein the first virtual machine ishosted by a first cloud server that hosts plurality of virtual machines,including: a memory; a network interface coupling to one or more cloudservers that host plurality of virtual machines in a hosted serviceenvironment and wherein the hosted service environment provides aninterface for capturing snapshots of the virtual machines hosted, eachsnapshot capturing a machine state including data volumes for thevirtual machine; one or more processors, coupled with the memory and thenetwork interface for performing: instructing the first cloud server tolaunch a recovery virtual machine; instructing the recovery virtualmachine to launch one or more new data volumes based upon captured filesystem images in one or more snapshots taken of corrupted data volumesof the first virtual machine prior to becoming corrupted; instructingthe recovery virtual machine to detach one or more corrupted datavolumes; and instructing the recovery virtual machine to attach one ormore new data volumes launched to the first virtual machine.
 2. Thesystem of claim 1, wherein the Internet Protocol address of the firstvirtual machine remains unchanged.
 3. The system of claim 1, furtherincluding halting the first virtual machine prior detaching corrupteddata system volumes.
 4. The system of claim 1, further includingrestarting the first virtual machine after attaching new data volumes.5. The system of claim 1, further including instructing the recoveryvirtual machine to launch a new root volume based upon captured filesystem images in one or more snapshots taken of corrupted data volumesof the first virtual machine prior to becoming corrupted.
 6. The systemof claim 5, further including instructing the recovery virtual machineto detach the first root volume.
 7. The system of claim 6, furtherincluding instructing the recovery virtual machine to attach the newroot volume launched to the first virtual machine.
 8. A non-transitorycomputer readable medium storing instructions for a first virtualmachine with an Internet Protocol address, a first root volume and oneor more data volumes that are corrupted; wherein the first virtualmachine is hosted by a first cloud server that hosts plurality ofvirtual machines, the instructions when executed by one or moreprocessors perform: instructing the first cloud server to launch arecovery virtual machine; instructing the recovery virtual machine tolaunch one or more new data volumes based upon captured data images inone or more snapshots taken of corrupted data volumes of the firstvirtual machine prior to becoming corrupted; instructing the recoveryvirtual machine to detach one or more corrupted data volumes; andinstructing the recovery virtual machine to attach one or more new datavolumes launched to the first virtual machine.
 9. The non-transitorycomputer readable medium of claim 8, wherein the Internet Protocoladdress of the first virtual machine remains unchanged.
 10. Thenon-transitory computer readable medium of claim 8, further includinghalting the first virtual machine prior detaching corrupted datavolumes.
 11. The non-transitory computer readable medium of claim 8,further including restarting the first virtual machine after attachingnew data volumes.
 12. The non-transitory computer readable medium ofclaim 8, further including instructing the recovery virtual machine tolaunch a new root volume based upon captured file system images in oneor more snapshots taken of corrupted data volumes of the first virtualmachine prior to becoming corrupted.
 13. The non-transitory computerreadable medium of claim 12, further including instructing the recoveryvirtual machine to detach the first root volume.
 14. The non-transitorycomputer readable medium of claim 13, further including instructing therecovery virtual machine to attach the new root volume launched to thefirst virtual machine.
 15. A method for recovering a first virtualmachine with an Internet Protocol address, a first root volume and oneor more data volumes that are corrupted; wherein the first virtualmachine is hosted by a first cloud server that hosts plurality ofvirtual machines, including: instructing the first cloud server tolaunch a recovery virtual machine; instructing the recovery virtualmachine to launch one or more new data volumes based upon captured filesystem images in one or more snapshots taken of corrupted data volumesof the first virtual machine prior to becoming corrupted; instructingthe recovery virtual machine to detach one or more corrupted datavolumes; and instructing the recovery virtual machine to attach one ormore new data volumes launched to the first virtual machine.
 16. Themethod of claim 15, wherein the Internet Protocol address of the firstvirtual machine remains unchanged.
 17. The method of claim 15, furtherincluding halting the first virtual machine prior detaching corrupteddata volumes.
 18. The method of claim 15, further including restartingthe first virtual machine after attaching new data volumes.
 19. Themethod of claim 15, further including instructing the recovery virtualmachine to launch a new root volume based upon captured file systemimages in one or more snapshots taken of corrupted data volumes of thefirst virtual machine prior to becoming corrupted.
 20. The method ofclaim 19, further including instructing the recovery virtual machine todetach the first root volume.
 21. The method of claim 20, furtherincluding instructing the recovery virtual machine to attach the newroot volume launched to the first virtual machine.